Display apparatus and method of operating the same



Nov. 18, 1930.1 G. A. WEARHAM 1,782,328

- DISPLAYJAPPARATUS AND METHOD OF OPERATING THE SAME Filed May 21, 1929 3 Sheets-Sheet l Nov. 18, 1930. G. A. WEARHAM 1,782,328

DISPLAY APPARATUS AND METHOD OF OPERATING THE SAME 5 Sheets-Sheet 2 Filed May 21., 1929 1212) ir J'Q.O1'1a42 :i ,1

G. A. WEARHAM Nov. 7 18, 1930.

DISPLAY APPARATUS AND METHOD OF OPERATING THE SAME Filed May 21', 1929 3 Sheets-Sheet Patented Nov. 18, 1930 Y "UNET'EDF rnras eg -P Q E" I GoRDon Auo srUs wE arrAr/r, or LONDON, EneLAnD DISPLAY .nrraaerusfnnnlrcarnon or ornnar rre THnsAMa Application filedlaiay a, ieeajseriai No. 264,854, and in GreatBritanLMay 2a; 1928'.

This invention, relates to. apparatus for use .-1n displaying matter of various kinds, such as advertisements, ;p1ctures,-not1ces;and artivcles of merchandise (hereinafter referred to generally as display matter) of the type V 'wherein. a container that contains a liquid screen, suchas an opaque milk-like liquid.

in combination with means operatingbyfiuid screen, has awall, e. g; a glass WZtlLCSHStltuting a window through which the said screen 1s visible, the thickness of which screen :is varied soas to change the appearance of.

the apparatus, as-by rendering display matter assoclate-d with the COIltEllIlGlTVlSlblQOl 1nv sible or changing its appearance when viewed through the window.

This lnvention has for one of its 01)]8Cts :to obviate theuse of actuating mechanism' built .into the containeryand to provide an; improved method .i'or'operating the apparatus in a more simplemanner than heretofore. Another object is to provide an improvedconstruction of apparatus of the type described'which shall be more. simple than (those made heretofore, shall occupy only a, relatively small space and can" he made at a low cost;

' According to an important feature oi. the" invention, there isprovided a method of operating display I apparatus of the type described, consisting in varyingthe thickness of the liquid screen,':tor example reducing.

it to zero, inthe chamber under the action or fluid pressure, such aspneumatic,hydraulic Such a method of or atmospheric pressure,

operation obviates the use of mechanisn'r built into the container and enables the apparatus to be convenientlyoperated "from a distance. I I

Accordlng to another nnportant feature ol the invention, there is provided a method of.

operatinga display apparatus of the type descrlbed whereln one of two opposed walls of the chamber situated in line with the display matter and having the liquid screen between them 1s flexible, consistingin'fiexing thickness 7 of ured from hack toliront of the invention, there. is provided apparatus of the type described comprising a container having. one side' wall (e, g. front walhycon stituting a window, through. which T display matter-may be viewed, and a liquid screen (e. g. of opaque liquid) situated in said container so as to be-visiblethrough the Window,

pressure (e. pneumatic,,,hydraulic or. atmospheric pressure)*for varyingthe thickness ,of said screen (e.g. reduclngit to zero) Qwingto the absence of mechanisnrbuiltinto the container 1 for actuating the. apparatus, the container. cairbe. made very thin as, measand can occupy only a. small space. i I

Inone construction according totheinvehtion, the wall constituting the window and the opposedwall (e g. rear wall) ;0f the container are both flexible and, are caused to approach towardssand recede from-:Qne

another under theaction of fluid pressure -(e. g. directly on the liquid in the container). 7 In another construction according tov'the invention, the. saidwall constituting the. window or the opposed wall-(e. g rear wall) of the container is flexible and the. other is rigid, .vvhich flexiblewallis causedt-o approach towards and recede from the rigid .wall under the action of fluid pressure the liquid in the container).

The said space for the liquid screenmay open below, accordingto another feature of the invention, into the lower part of a storage compartment containing. liquid, which compartmenthas means for exerting pressure on theliquid therein and thereby lifting liquid ji-nto said space for 'operatingthe apparatus.

Alternatively, the said space for liquid. mayonenv above, accord ng to another, fea- "ture of the invention, into the lower part of a storage compartment containing liquid, which compartment has means for reducing the pressure on the free surface of the liquid in said compartment and therebylifting 2 liq'uidout of said space, for operatingthe apparatus l "According to yet another feature of the invention, a plurality of containers-,forexample two thereof, each as described above,

(e. g. directly on construction of the apparatus will be described hereinafter and pointed out in the claims.

Several forms of apparatus. according to theinvention and adapted for carrying the described methodinto practice are diagrammatically illustrated by way of example in the accompanying drawing, where1n:

Figures 1 and 2 are front elevations of one 'form of display sign according to the invention, respectively showing the display matter visible andinvisible from the front of the sign, and

Figure 3 is a diagrammatic vertical trans-' verse section, on an enlarged scale, taken through the same i cross-section corresponding to Figure 3 showing various other constructions of display sign according to the invention, and

"Figure 10 is a side elevation of a detail.

Like reference characters designate like parts throughout the several views.

1 Referring first to Figures 1 to 3, the display sign comprises a rectangular frame 15 of wood, metal or other convenient material,

" carrying a sheet of glass16 constituting a window secured fluid tight asby a groove 17 in the frame. Behind the glass 16 and pref erably parallel therewith is a flexible diaphragm 18 which may be transparent, translucent or opaque, and may be a thin sheet of celluloid metal orother convenient material. This diaphragm 18 is mounted fluid tight in the frame .15 as by a groove 19, so as to form with the glass 16 and frame 15 a container,

designated generally 20, whereoffthe glass window 16 is the front wall and the dia- "phragm 18 is the opposite rear wall.. These two walls may be placed at any convenient distance apart, say so that the space 21 between them is quite narrow to enable the middle portion of the diaphragm 18 when fiexedas described hereinafter to lie flat against or closeto the middle of the window 16.

' The upper part of the frame 15 is formed at the rear as a compartment 22 which opens below into the space 21 and has above an outlet 23 which can be secured by a tube 29 to any convenient intermittentlyoperated suction device'24, such as a suction pump.

This compartment 22 serves for storing an opaqne-, semi-opaque, translucent or trans parent liquid 25 which may be coloured and which fills the space 21 and there constitutes Figures 4, 5, 6, .7, 8 and 9 are views in a liquid screen between the front and rear walls of the container 20.

The matter, such as words or a design, to be displayed may be carried on either side of the diaphragm 18 if the latter is transparent, and may be embossed, engraved, printed, stamped, stenciled or photographed thereon, or otherwise applied thereto. hen the diaphragm 18 is opaque the display matter will be on its front face and may be in the form of yielding material 26, such as rubber, shaped to form letters for example, and adapted to bed tightly against the glass 16. A mount 27, which may he of cardboard or other convenient material, or be constituted by a coatof paint or the like on the glass, may be arranged in front of the glass 16 to screen off from view the greater part of the diaphragm 18 and the liquid surrounding the display matter.

' Assuming that the liquid 25 is milk-white and so opaque as to obscure the display matter when viewed through the window, the display sign will have the blank appearance shown in Figure 2. When the suction device Ztoperates to reduce the pressure in the compartment22, atmospheric pressure acting on theback of the diaphragm 18 will flex the latter and gradually press the display matter 26 into contact with the glass window 16 and thereby render it clearly visible, as shown in Figure 1. On the return stroke of the piston the diaphragm 18 will return to lts nor- .mal )osition s aaced awa T from the lass 16 and the liquid will again obscure the display matter 26.

lVhen the liquid 25 is tinted and transparent, the display matter will also preferably be coloured, and the colourof the liquid may contrast with and be complementary to the colour of the display matter. For-example, if the display matter is in the form of yellow letters and a blue liquid is used, then when the thickness of the liquid screen varies the colour of the sign will change gradually from a green to a yellow when the letters are pressed tightly against the glass. Alternatively red letters may be used with a green liquid when the letters will normally appear black and will gradually change to red.

- Instead of the above described arrangement of the display matter, such matter, for example in the form of a stencil or transparency, may be wholly or in part provided on the window at the front or rear thereof. If it is on the front of the window the front face of the rear wall will preferably be coloured or it may also carry some display matter.

When both the front and rear walls 16. 18 of the container 20 are transparent the display matter may be arranged at the of the container so as to be viewed through both of the walls. It may be arranged on the rear face of the diaphragm 18 or spaced away from the same, in which case actual articles of merchandise, suclras ribbons of va-. -r1ous colours,-may-serve' as display matter. If a source'o'f-light such as an electric light,

' the glasslfland the' flexible diaphragm 18. Display matter36 'isf'shown moulded on the diaphragm 185 and the space 21 remains filled with liquid 'butjvaries in size. VJhen the pump operates, the diaphragm 18 is flexed alternately away from and towards the glass '16. If desiredythe compartment 33 and tube inFi'gure 3 may. always spaced'a-way therefrom as shown, or close to V it, a vent hole 38being arranged to connect.

31 may always befllled with;liquid; Simi- *larly the compartment'- 22 and tube 29 shown In thisaconstruction, and in thatshown inFig ure 3; a backboard or a third sheetef transparent; translucent or opaque material may be arranged behind the diaphragm 18, either the space '39'bet-weenthe two walls 18, 37 with the atmosphere so as to allow the diaphragm 18 to flex freely.

' The display sign shown in Figure 5 has an upper storage chamber22 and a lower pressure chamber 33, but-the latter opens into an otherwise closedspace 39 between the walls j v 18' 37 and not'into'the space 21 as in the sign ily flexible asby corrugations shown at 4O.

i may be driven by any convenient shown in Figure 4. When air or other fluid under pressure is intermittently supplied to. the inlet*32'thediaphragm 18 will be moved towards and away fromthe glass window'16 to change-the appearance oiith'e display matter or to render 1t visible and 1nv1s1'ble. In

order to facilitate the movement of the dia-- phragm 18in this construction and in those shown in Figures 3 and 4the marginal portions of the diaphragm may 'be'rendered read- Alternatively, the diaphragmanayrbe resiliently suspended in any convenient'fluid tight manner, as by means of a marginal portionot india-rubber-or other flexible mate rial. The rear wall 37 is transparent and the display matter 46 is carried by an endless band4-1 arranged round tworollers 42 which to move the display matter across-the line of vision through the window 16. This band 41 maybe transparent, and electric lamps 43 may be arranged within it or at some other position so as to illuminate thedisplay matter or parts of the sign surrounding the latter, for example, n some cases a lampmaybe arranged in the chamber 22 to throwlight f downwards into theliquid screen in the space 21. A filter 44 may be arranged in the'comlow 'air to escape phragm' 18 is flexed, but compartment may have a flexible commodate various quantities of liquid in it In this be filled with liquid.

a filling plug 53. is provided.

mechanism partment to prevent dust I from -colleoting in thespace 39. A mount 27 rwhich'may be described hereinafter is a; coat of paint as so that only one secpret'erably arranged tion of the display matter'46 is visible through the window 16 at one time. A vent 28 is preferably provided in the compa-rtment22 to altherefrom when the diainstead thereofthis wall to ac- ,Without causing undue pressure. construction thew'alls 18 and 37 enclosing the space 39 constituting an actuating chamber,:designated generally 47, arranged to be subjected to air pressurqthe diaphragm '18 being common to thetwo chambers 20 and arran 'ed'one in front of the other. 'Instead of. actuatin this si n b fluid ressu're b D i it may be actuated-by intermittently evacuating the actuating chamber 47 ,by means of a the chamber 33. Alternatively, which maybe coloured may beused instead ota gas in the coritainer'47forflexirig the diaphragm 18. 1 r l "The sign shown in Figure 6 has an actuating chan'iber in the form of anexpansible arranged be-- bag 48,- for example an a-ir bag,

tweenthe middle of the diaphragm 18 and a back wall 37 ofthe'sign. 'Thisbag 48 may be operated bya gas or liquid by means of an indie-rubber bulb 49 or other pressure or suction device connectedwiththe bag by a tube which may be provided withan audible signalling device, such as a whistle 7 51, to make a sound whenever the sign'is operated. In ordertodistribute the pressure of the bag 48 evenly over the adjacent portion of the diaphragm 18 a sheet of rigid materialysuch as a piece or" sheet aluminium 52 may be interposed betweenthe diaphragm 18 and the bag 48u ll -lion the middle portion of the dia-- phragm 18 is flexed towards the window 16 otherfparts oi the diaphragm will be flexed away therefrom I ,toaccomniodate the displaced liquid. For fill ng the container 20 Figure 7 shows a display sign comprising two containers 20 arranged one in front of "the other/ with their diaphragms 18 placed baok to back but spaced apart one from the other to provide a space 60 which'may constitute'or accommodate an expansible actuating chamber. As illustrated a bag 61', which may contain gas or liquid, has opposed walls each bearing against one of the diaphragms 18, and serves to vary thethickness of the liquid screensin the two containers in un1-' son when the bag is expanded and allowed to contract by fluid pressureto which it i's subjected by any convenient means. Each'of the liquid spaces 21 opens above into astorage chamber 62 com'mon'to them botn and having a vent 63. Display matter 26 may be suction device connected to the outlet 320i a liquid arranged onthe diaphragms 18 or, if they are transparent, on the outside of the air bag '61. 7 Alternatively, the bag may be composed I of transparent material as well as the dial phragm'18, in which case the display matter may be arranged inside the bag.

In the display sign shown in Figure 8 a container consists oftwo circular transparent walls 65, 66 of flexible materialliavmg their marginal portions ]O1l1(:Cl together to form a circular bag which when filled with liquid 67 1 constitutes a magnifying lens. As illustrated this bag has at the topa liquid supply tube 68 by which it is supported in the frame 15, and

t it is resiliently anchored atthe bottom to the frame by one or more springs69 to allow for its contraction and expansion when the quantity of liquid in it varies. Two sheets of glass 70, 7l may be arranged one at each side of the bag in the frame, and the display matter 72 maybe carried on one or both windows 70, 71,01 it nay be placed at any convenient {llS- tauce from the display sign so as to be viewed "through-it. The marginal portions of the wall. 65,- 66 of the bag are preferably corrugated, and mounts27 may be arranged to hide such corrugations.

Figure 9lshows a display sign comprising a container havingbehind it a closed actuating chamber 47 containing either a or liquid, the rear -wall,37 of which actuating chamber is flexible, and carries .a massive body in the form of a metal weight. When such a sign is mounted on a movable support,

- such as a motor driven vehicle, and is arranged facing the dlrectlon of travel, the

inertia of the weight 55 will serve to vary the pressure of theair in the actuating chamber 47 and thereby vary the thickness of the liquid screen in the space 21, when the rate of movement of the vehicle varies. For example, if the vehicle stops suddenly the weight 55 will. move towards the liquid screen and reduce its thickness, and will subsequently move away from the screen, thereby changing theappearance of the sign.

Instead of or as well as using this weight 55 the wall 37 may be flexed by any convenient mechanical means, such as a cam 56 arranged to move it toward and away from the liquidscreen.

Figure 10 shows a modified form of actuating device foroperating the display sign under the action of fluid pressure varied by the inertia of a movable mass. In this con struction the movable mass IS a body of mercury 75 constituting a piston movable freely in a cylinder 76 in the form of a'U -tube, and

I through the Win a conduit '77 which may contain gas or a liquid serves to connect the cylinder 7 6 with the display sign. This actuating device may be used instead of any of the operating devices described above in an analogous manner.

In any ofthe constructions of display sign described above the whole or part of a diaphragm 18 opposed to a window 16, or display matter on the inner face of a diaphragm 18, may be coated with a self-luminous composition. In order to prevent the liquid on the sign freezing in cold weather an ingredient, such as glycerine, may be added'to it may be arranged not parallel to one another but at a small angle so that contact between the window and the opposed wall will be effected gradually along the height or length ofthe same. Alternatively, the wall 18 may be moulded or shaped for the same purpose, or display matter fixed to the saidwall may vary in thickness.

Any of the display signs described above maybe provided in front of the Window with a coloured screen of transparent material, such ascelluloid, as shown at 127 in Figure 5. Such a screen may have a coating of paint 27 on a face of its marginal portion to constitute amount. Alternatively this mount may consist of cardboard or other sheet material.

Any convenient safety device, for example a valve, may be provided for the pressure or suction compartments referred to above to prevent undue pressures therein.

A reflector may be arranged in a display sign as described above so as to be visible dow. For example, in the construction shown in Figure 3, part of the front face of the flexible wall 18 may consti- .tnte or be provided with a reflector.

I whichwalls constitutes .a window through with .a liquid-screen between them, one of which the screen is visible, and atleast one of which walls is ing a flexible wall of'the, container towards and away from its opposedwall under the.

to change the appearance ofthe-apparatus. 3. Display apparatus comprising a container having one wall constitutinga window,

andliquid constituting a screen situated in the container so as tobe visible through the window, in combination with meansoperatsaid walls,

I 6. In display walls, which ingby fluid pressure arrangedto vary the amount of liquid: situated in theline of vision through the window. I I

4. Display apparatus comprising a container having two opposed. walls and a liquid screen between them, one of which walls constitutes a window and atleast one of which walls is movable towards and away from the other wall, in combination with'means operating by fluid pressure. arranged to move a said movable wall towards and away from its opposedwall and thereby vary the thickness of the liquid screen.

5. Display apparatus comprising. a container having two opposed walls and a liquid screen between them, one of which walls constitutes a window, and at least one .ofiwhich walls is flexible and movable towards and away from the other, wall, in combination with means operating by fluid pressure arranged to flex asaid flexible wall towards and away from its opposed wall and thereby vary the thickness of theliquid screen.

apparatus of the character described, a container having two opposed walls spaced apart,'a liquid screen between one of which walls constitutes a window, and one of which walls is flexible and movable towards and away from the other wall, and a storage compartment for supplying liquid to and receivingliqui'd from the space between said walls.

7. In display apparatus of the character'described, a container having two opposed walls spaced apart,'a liquid screen be tween j said walls, oneof which walls constitutes a window, and one of which wallsjis flexible and movable towards and away from the other wall, and a storage compartmentfor liquid opening into the space between said compartment has an inlet for connectionto means for varyingthe fluid pressure in said compartment.

8. In display apparatus of the'character described, a container having two opposed vert1cal walls spaced apart, a liquid screen between said walls, one of which walls constitutes awindow, and one-of which walls is movable towards and away from the other of said walls, and a storage compartment for flexible, consisting in flex-.

. tween said walls, tutes a window, and oneoi which" walls is movable'towards and away from the'opposed the top of the spacebe-' fluid ,pressu refor moving the movable wall andv thereby causing liquid to be supplied from said. space to the storage chamber and reversely; a

. 9. Display apparatus comprisingin combination a container whereof one wall consti-* tutesa window, and anopposed wall is movable towards and away therefrom,a liquid. screen in the containerbetween the opposed walls, and an actuating chamber. operatedby fluid pressurearranged to move said movable vall towards and away from the window.

10'. Display apparatus comprising in combination a container whereofone wall consti tutes a window, and an opposed wall istran s lucent, liquid constituting a screen; oc up ing thespace between said walls, and means operating by fluid pressure arranged to vary.

the amount of liquidv situated'in the line-of vision throughthe window and said opposed wall.

11. Display apparatus comprising in com 1 binationa container, whereof one'wallconst-itutes a window, andan opposed wall is translucent, liquid constituting a screen occupying the space between said walls,'one ofwhich walls is movable towards and away from the other, and an actuating chamber thatv has translucent walls situated in the line of vision through said opposed walls, and operated by fluid pressure,

bination a container, whereofone wall constitutesa window, and an opposed wall is trans.

and is arranged. to vary the thickness ofsaid screen by moving themovable wall of the container.

tween said walls, and means operated by; i

lucent, liquid constituting a screen, occupying the space between said walls, one of which walls is movableltowards andjawayfrom the other, means by movingthe movable wall of the container, and display matter mounted to move. transversely across the line ofvision throughsaidv window. 13. In display walls spaced apart, a tinted liquid screen be one" of which wallsfconstiwall," and means operating by fluid pressure 5 operated by fluid pressure and arranged. to vary the thickness of said screen apparatus of the character described, a container having-two opposed,

arranged to vary the thickness of said screen.

display apparatus of the character described, a'container having two opp sed.

walls spaced apart, a tinted liquid screen between :said walls',j"one of which walls con-, stitutes a window, and one of which walls is movable towards and away from the opposed wall, means operating by fluid pressure ar'- .to vary the thickness of .saidscreen, I the wall opposed to said window having associated with ,it tinted display. matter arranged to .be viewed through said window',-

ranged and means fluid pressure in the space between said walls the tint of which liquid is of a colour that contrasts with the colour ot the display matter.

. l5. Display apparatus comprisingin combination acontainer having one wall constituting a window, liquid that containsaningredient for lowering the freezing point thereof, cons ituting a screen situated in the container so asto be visible through the window, and means operating by fluid pressure arranged to. vary the amount of liquid situated in the line of vision through the window. 16; In display apparatus ofthe character described, a container having two opposed walls spaced apart, a liquid screen between said walls, one of which. walls constitutes a Window, and one of which walls is flexible and movable towards and away from the other wall, a storage compartment for liquid opening into the space between said walls, for intermittently reducing the to below atmospheric pressure. r

1 7. In displaygapparatus of the character described, a container having two opposed walls spaced apart, a liquid screen between said walls, oneof which walls constitutes a window, and one of whiclrwalls is flexible and movable towards and away from the otherwall, a storage compartment for liquid opening into the bottom of the space between said walls, and means for intermittently exerting fluid pressure on'the liquid in said storage compartment and thereby intermittently moving the flexible wall towards and away from its opposed wall. g

' 18. In display apparatus of the character described a containerhaving two opposed iii walls spaced apart,-a liquid screen between said walls, which walls are both transparent and flexible and movable each towards and away from the opposed wall, and means oper- 'ating' by fluid pressure arranged to vary the amount of liquid situated in the line of vision through said walls, which container together screen therein, constitutes 'a lens-like structure when its transparent opposed Walls are caused to rccede from one another. V V p 19. In display apparatus of the'character described, a container having'two opposed walls spaced apart, a liquid screen between saidwalls,'one of which walls constitutes a window, and one of which walls is movable towards and away from the opposed wall,

the inner faceof one of said walls having displaymatter composed ofyielding material mounted on it and arranged to contact with the inner face of the otherwall.

20. Display apparatus comprising a con tainer having one wall constituting a window, and liquid constituting a screen situated in the container so as to be visible through the window, in combination with means operating by fluid pressure arranged to vary the amount of liquid situated in the line of visionthrough the window, and an acoustic signalling device arranged to be actuated by the fluid pressure serving for varying the thickness of the liquid screen.

21; Display appartus comprising in com- GORDON AUGUSTUS l/VEARHAM. 

